Rotary piston engine and piston phasing apparatus therefor

ABSTRACT

The apparatus controls relative motion between the rotary pistons of a rotary piston engine by the use of a curvilinear internal ring gear the contour of which is determined by the desired compression ratio of a variable volume defined between adjacent rotary pistons. Pinions, suitably connected to the rotary piston, traverse the contour of the curvilinear internal ring gear while constrained to move radially with respect to the axis of rotation and constrained in a constant angular relationship with respect to one another. The rotary piston shape disclosed uses centrifugal force to assist sealing engagement of compression rings with walls of the piston cavity. Inlet and exhaust ports may be positioned such that the apparatus may be used to control piston movement of an internal combustion engine, a pump, a compressor, a turbine, or a motor.

United States Patent 1191 Dailey Apr. 8, 1975 1 1 ROTARY PISTON ENGINEAND PISTON PHASING APPARATUS THEREFOR [76] Inventor: Alvin Bailey, 4527New Hampshire Ave. N.W., Washington. DC.

[22] Filed: Jan. 4. I974 1211 Appl. No.: 430,923

Primary E.\'aminer.lohn .1. Vrablik Attorney, Agent, or Firm-Burns.Doane Swecker 84 Mathis {57] ABSTRACT The apparatus controls relativemotion between the rotary pistons of a rotary piston engine by the useof a curvilinear internal ring gear the contour of which is determinedby the desired compression ratio of a variable volume defined betweenadjacent rotary pistons. Pinions. suitably connected to the rotarypiston, traverse the contour of the curvilinear internal ring gear whileconstrained to move radially with respect to the axis of rotation andconstrained in a constant angular relationship with respect to oneanother. The rotary piston shape disclosed uses centrifugal force toassist sealing engagement of compression rings with walls of the pistoncavity.

lnlet and exhaust ports may be positioned such that the apparatus may beused to control piston movement of an internal combustion engine. apump. a compressor, a' turbine. or a motor.

14 Claims, 16 Drawing Figures namin -a ems, 3.876.342

ROTARY PISTON ENGINE AND PISTON PHASING APPARATUS THEREFOR BACKGROUND OFTHE INVENTION 1. Field of the Invention The invention relates tocontrolling the relative motion between rotary pistons of a rotarypiston device. such as an internal combustion engine in which all rotarypistons move in the same general direction of rotation but have relativemotion therebetween.

Description of the Prior Art U.S. Pat. No. 3.476.056 issued tojames A.Bright on Nov. 4. I969 discloses a pump having oscillating vanes whosemotion is controlled by a planetry gear system wherein the pinions areprovided with an eccentric pin which engages a slot of a plate connectedto one set of rotary vanes. The construction of the Bright patent,however. with its slender eccentric pins to transmit roatry motion.comprises a fragile means of creating the necessary oscillatory motionand is not well suited to internal combustion engines. Other proposalsto create oscillatory motion between rotating pistons are illustrated bythe patent issued to William McMahon. U.S. pat. No. 3.730.654 on May 1.I973, and the patent issued to Hans Schudt. U.S. Pat. No. 3.398.643 onAug. 27. I968. The Schudt and Mc Mahon patents are illustrative ofeccentric gearing arrangements between the shafts carrying theoscillating rotary pistons which require specially-fabricated complexgears. The gears. in addition to being noisy. must be provided withextremely close tolerances to provide reliable operation. Moreover. theeccentric gear of the Schudt patent are not well suited for deviceshaving a high angular velocity since dynamic balancing becomes aproblem.

U.S. Pat. No. 1.556.843, issued to Cloyd L. Kinder on Oct. 13. I925.discloses a rotary piston device wherein the motion of one ofthe rotarypiston elements is varied with respect to the constant motion of asecond rotary piston element by means of a cam-slot ar rangement. Thecam-slot arrangement of Kinder does not. however. accomodate oscillatorymotion of both piston elements. In addition. the Kinder apparatus wouldbe exceptionally difficult to balance dynamically for high speedrotation.

US. Pat. No. 3.075.506. issued to Frank Berry on Jan. 29. I963.discloses a spherical trajectory rotary power device which is porvidedwith a threedimensional cam groove to control the oscillatory rotarymotion ofpiston elements therein. The cam groove of the Berry patent,however. would be exceptionally difficult to fabricate in view of itsthree-dimensional character.

SUMMARY OF THE INVENTION The instant invention provides a durable.compact phasing apparatus for controlling the oscillatory motion of apair of rotary piston elements and a rotary power shaft. The phasingapparatus is particularly well suited for an internal combustion engine.A phasing member provided with a curvilinear internal ring gear is usedto control the relative motion between rotary piston elements. Two pairof equiangularly spaced rotary pinions are provided which mesh with theinternal curvilinear ring gear. The two pair of rotary pinions areconstrained to move radially with respect to the axis of rotation of therotary power shaft. Each pair of rotary pinions are interconnected withone of the rotary pistons through a simple gear and shaft mechanism. Thesymmetrical arrangement of the rotating parts provides an assembly whichis well suited for dynamic balancing.

The use of pistons which move in the same general direction but whichoscillate with respect to one another. reduces the amount of otherwiseuseful energy which would be wasted in conventional reciprocating pistonarrangements.

The phasing apparatus design allows easy modification of the compressionratio of a space defined between adjacent pistons for any suitableapplication.

The piston shape disclosed allows centrifugal force to assist sealingengagement between compression rings and the piston chambers.

BRIEF DESCRIPTION OF THE DRAWINGS The detailed description of apreferred embodiment of the invention makes reference to theaccompanying drawings in which:

FIG. 1 is a perspective view of an internal combos tion engine;

FIG. 2 is an exploded perspective view of several basic elements oftheinvention as they would appear in FIG. I with the housing removed;

FIG. 3 is a cross-sectional view taken through a generally verticalplane as illustrated by line 3-3 in FIG. i;

FIG. 4 is a cross-sectional view taken along line 4-I of FIG. 3;

FIGS. 5. 6. 7 and 8 are cross-sectional views taken along line 55 ofFIG. 3:

FIGS. 5A. 6A. 7A and 8A correspond to each of FIGS. 5 through 8 andillustrate the corresponding positioning of fundamental elements ofthetiming mechanism;

FIG. 9 is an enlarged view of the belt tensioning mechanism which isillustrated in smaller detail in FIG.

FIG. I0 is a halfelevation along centerline Ill-1011f FIG. 1;

FIG. 11 is partial elevation of one rotary piston; and

FIG. 12 is a cross-sectional view along line 12-12 of FIG. 9.

DETAILED DESCRIPTION OF THE INVENTION The compact external configurationof an internal combustion engine which employs the novel phasingmechanism of this invention is illustrated in FIG. I. In the interest ofclarity. such conventional devices as carburetion. cooling systems.ignition systems. and starting mechanisms are not shown. A housing 20 isprovided which includes a front cover plate 22, an intermediate housing24, a rear housing 26 and a rear cover plate 29. Rear cover plate 29 issuitably secured to flange 28 of rear housing 26 to provide access torotary plate 94. Flange 30 of the rear housing 26 is suitably fastenedto flange 32 of intermediate housing 24 and thus allows access tophasing cavity 54. Flange 34 of intermediate housing 24 is suitablyfastened to flange 36 of front cover plate 22 to allow access to pistoncavity 52.

The front cover plate 22 is provided with a pipe 38 through whichcoolant is admitted to a cooling jacket to be described more fullyhereinafter. Intermediate housing 24 is provided with a pipe 40 throughwhich coolant is removed from the cooling jacket. The inlet and outletmay however. be reversed such that pipe 40 is the inlet and pipe 38 isthe outlet.

A rotary power shaft 42 protrudes from housing through rear cover plate29. Shaft 42 may be connected to any suitable device such as atransmission (not shown) when the apparatus of the instant inven tion isused an an internal combustion engine. When the apparatus is used as apump, shaft 42 is a power input; when used as a motor, shaft 42 is apower output shaft.

inlet ports 44 are provided in front cover plate 22 to admit acombustible mixture to the internal combustion engine from a suitablecarburetor (not shown). similarly, exhaust ports 46 are provided infront cover plate 22 to permit the exhaustion of gases from the internal combustion engine. A spark plug 48 is provided in the front coverplate 22 and is connected to a suitable ignition system (not shown). Thecoolant inlet pipe 38 and coolant outlet pipe 40 may be connected to asuitable radiator and coolant recirculation system.

The relationship between the internal combustion engine components. thephasing mechanism, and the housing 20 is clearly shown in FIG. 3. Acooling jacket or cavity 50, 56 is provided in the housing 20 to coolthe combustion chamber and to cool lubricating oil disposed withinphasing cavity 54. Cooling cavity 50 provided in the front housing cover22 and cooling cavity 56 is disposed within the intermediate housing 24.The front housing cover 22 and the intermediate housing 24 also define apiston cavity 52. Moreover, housing 20 defines a phasing cavity 54 towhich access is provided through flanges 30, 32. Cooling cavities 50, 56comma nicate with one another through openings 58 provided in flanges34, 36 thereby allowing a continuous circulation of coolant to pass frompipe 38 to pipe 40.

A plurality ofthe exhaust ports 46, illustrated in FlG. 3, communicatewith the piston cavity 52 through conduits 55 which pass through coolingcavity 50. Intake ports 44 are similarly provided with conduits 55 thatcommunicate with piston cavity 52.

A first rotary piston element 60 and a second rotary piston element 62are disposed within the piston cavity 52. The first rotary pistonelement 60 is connected to one end of an inner coaxial piston shaft 64which is disposed within the piston cavity 52. Each rotary pistonelement 60, 62 is provided with a pair of piston faces to be more fullydescribed hereinafter. The second rotary piston element 62 is attachedto one end of an outer coaxial piston shaft 66 which protrudes into thepiston cavity 52. The rotary piston elements 60, 62 may also beintegrally connected to the respective coaxial piston shaft 64, 66. Theinner coaxial piston shaft 64 and the outer coaxial piston shaft 66 maybe provided with suitable bearings therebetween and between therespective shafts and housing 20. The bearings may be roller bearings orball bearings and are considered to be a matter of design. Likewise,suitable gaskets may be provided as required. One end of the innercoaxial piston shaft 64 and one end of the outer coaxial piston shaft 66protrude ii13lo the phasing cavity 54. The inner coaxial piston shafi isjournaled, or otherwise mounted for relative motie/n, in the end 43 ofroatary power shaft 42. The end of puter coaxial shaft 66 whichprotrudes into phasing calvity 54, is provided with a driving gear 70.Similarly, I e inner coaxial piston shaft is provided with a driving ear72.

The means hereby the coaxial piston shafts are interconnected ill now bedescribed in detail. This interconnecton means comprises a pistonphasing mechanism which, as noted above, is suitable for any rotarypiston device. For the purposes of this discussion, FIGS. 2, 3 and 4 aremost helpful in visualization of the apparatus to which reference ismade.

At the heart of my phasing mechanism is a phasing member which isillustrated in FIG. 3 as an integral portion of rear housing 26. Itshould be noted, however, that the phasing member could be removablyconnected to the housing member 26 in any suitable fashion, for example,by being bolted therto. The phasing member 80 is provided with a phasingopening 82 which defines a curvilinear opening that has gear teeth 83thereon. The phasing member 80 thus defines a generally curvilineartwo-dimensional internal ring gear. The phasing member 80 is providedwith raised machined surfaces 84, 86 on the front and rear surfacesthereof. The function of these surfaces will be described in more detaillater. As illustrated in FIG. 4, four pinions 88 are provided which meshwith the teeth 83 of phasing opening 82. Each of the four pinions 88contacts the phasing opening 82 at a different point thereon. Eachpinion 88 is securely mounted on a pinion shaft 90 which is rotatablysupported by a first rotary plate 92 and a second rotary plate 94. Thephasing member 80 is disposed between the first rotary plate 92 and thesecond rotary plate 94, in the preferred embodiment, so that the pinionshaft may be simply supported. When so desired, the first and the secondrotary plates 92, 94 may be provided with arcuate cutouts as illustratedin FIG. 4. The arcuate cutouts 100 of the first rotary plate 92 define aplurality of peripheral portions 98. Between each of the peripheralportions 98 of rotary plates 92, 94, and the phasing member 80, abearing 96 is provided which coacts with machined bearing surfaces 84,86 of the phasing member 80 to support and position the rotary plates92, 94.

Both the first rotary plate 92 and the second rotary plate 94 areconnected to the rotary power shaft 42 such that the plates and theshaft are constrained to rotate simultaneously. A spacer 95 isconcentrically provided on the rotary powcr shaft to accurately positionthe first and second rotary plates 92, 94. Each rotary plate 92, 94 isprovided with a plurality of radial slots 102. The radial slots 102 ofthe first rotary plate 92 and the slot 102 of the second rotary plate 94are axially aligned. Each radial slot 102, receives one end ofa pin ionshaft 90 which is rotatably mounted in a carriage means 104 that slideslongitudinally of the radial slot. The radial orientation of the slots102 constrains each pinion 88 and associated pinion shaft 90 to move ina radial direction only.

It will be noted that the gears to be described are illustrated on theFigures as conventional offset bevel gears which permit powertransmission between nonintersecting shafts. A modification to bedescribed hereinafter may use conventional bevel gears.

The driving gear 70 attached to the outer coaxial pis ton shaft 66meshes with a first fixed driven gear which is attached approximately atthe center of a first splined shaft 112. Splined shaft 112 isperpendicularly aligned with respect to the axis of the coaxial pistonshafts 64, 66. The first splined shaft 112 is rotatably supported byshaft mountings 113 disposed at each end thereof. The shaft mountings113 are suitably mounted on the first rotating plate 92. A firsttranslating gear 114 is disposed between the fixed driven gear 110 andone end of shaft 112. The translating gear 114 is provided with asplined bore which permits the translating gear 114 to slidelongitudinally along splined shaft 112. Shaft 112 drives the firsttranslating gear 114 in accordance with the rotary motion imparted toshaft 112 from coaxial piston shaft 66 through the gears 70, 110. Asecond translating gear 116 is disposed between the fixed driven gear110 and the second end of splined shaft 112 and is similarly driventhereby. The first translating gear meshes with a first pinion drivinggear 118 which is attached to one end of one pinion shaft 90. A secondpinion driving gear 120 meshes with the second translating gear 116 andis attached to another pinion shaft 90. To maintain meshed engagementbetween the first translating gear 114 and the first pinion driving gear118, an L-shaped member 122 is provided. The L-shaped member 122constrains the meshed gears 114, 118 to be constantly in mesh whilepermitting relative rotation between each gear 114, 118 and the L-shapedmember 122. A similar L-shaped member 122 is provided for the secondtranslating gear 116 and the second pinion driving gear 120 which meshestherewith.

Analogously, the inner coaxial shaft 64 drives the driving gear 72 whichmeshes with a second fixed driven gear 124 carried by a second splinedshaft 126. The second splined shaft 126 is rotatably mounted on shaftmountings 128 each of which is suitably secured to the first rotatingplate 92. The second splined shaft 126 is perpendicular to the innercoaxial shaft 64 and is also perpendicular to the first splined shaft112. The first splined shaft 112 and the second splined shaft 126 arenot, however, coplanar as may clearly be seen from FIGS. 2 and 3. Athird translating gear 120 is slidably mounted on splined shaft 126 in amanner similar to that whereby the first translating gear 114 is mountedon first splined shaft 112. Similarly, a fourth translating gear 132 isslidably mounted on shaft 126 in the same fashion that translating gear116 is mounted on shaft 112. The third translating gear 130 meshes witha third pinion driving gear 134 carried by a pinion shaft 90; the fourthtranslating gear 132 meshes with a fourth pinion driving gear 136carried by the remaining pinion shaft 90. An L-shaped member 122maintains meshed engagement between gears 130, 134 and another L- shapedmember 122 maintains engagement between gears 132, 136.

A first gear ratio R. is defined by the number of teeth on a fixeddriven gear (110 or 124) divided by the number of teeth on a fixeddriving gear (70 or 72). A second gear ratio R is defined by the numberof teeth on a pinion driving gear (118, 120, 134, or 136) divided by thenumber of teeth on a translating gear (114, 116, 130. or 132). A thirdgear ratio, R is defined by the number of teeth on the internal ringgear (82) divided by the number of teeth or a pinion 88. The product ofthe first and second gear ratios must equal the third gear ratio. i.e. R=R X R so that each pinion will make one complete traversal of phasingopening 82 for each complete revolution of rotary piston elements 60,62.

To ensure meshed engagement between the pinions 88 and the teeth 83 ofphasing opening 82, a first tensioning band 140 and a second tensioningband 142 are provided. One end of each tensioning band is secured to onepinion shaft 90 between the pinion driving gear thereon and the firstrotating plate 92 by any suitable means. First tensioning band 140interconnects two pinions 88 in adjacent radial slots 102 which pinionsare driven by pinion driving gears and 134. Second tensioning band 142interconnects two pinions 88 which are driven by pinion driving gears118 and 136. At each peripheral portion 98 of the first rotary plate 92,a spring-biased tensioning pulley 144 is provided, typically asillustrated in FIG. 4 by reference 143.

FIG. 9 illustrates one of the many devices whereby tensioning pulleys144 may be mounted on rotary plate 92. A pulley support 190 has aC-shaped configuration and is provided with two longitudinal slots 192.Pulley 144 is mounted on a pulley shaft 200 that is supported in holes202 of a pulley cage 196. The ends of pulley shaft 200 protrude throughpulley cage 196 and are received within longitudinal slots 192. Pulleycage 196 is provided with a pair of pins 198 which are likewise receivedby longitudinal slots 192. Biasing spring 194 resiliently urges thepulley cage 196 and the pulley 144 carried thereby toward the peripheralportion 98 of the rotary member 92. The pins 198 and the protruding endsof pulley shaft 200 engage the longitudinal slots 192 and guide thetranslatory motion ofthe pulley 144.

A dynamic balancing means 146 may be disposed at the peripheral portions98 of the first rotating plate 92 to accommodate rotational imbalancedue to the placement of the non-coplanar splined shafts 112, 126. Thedetail of the balancing means is a matter of design which is notrelevant ot the disclosure of this invention.

Each rotary piston element 60, 62 includes a pair of diametricallyopposed piston faces 150, 152 and 154, 156, respectively. Depending fromeach of the diametrically opposed piston faces 150, 153, 154, 156 is asegmentally shaped skirt 158 which is shown most clearly in FIGS. 2 and5. The planform of each piston face 150, 152. 154. 156 includes a pairof straight converging sides 160, 162 which are tangent to a generallycircular portion 164 at the radially outermost portion thereof. Thepiston cavity 52 is circular when viewed along the line 5-5 of FIG. 3and the cross section thereof is similar to the planform of the pistonfaces 150, 152, 154, 156.

Compression rings 16] are retained in ring grooves 160 provided on skirt158 depending from each piston face 150, 152, 154, 156 as typicallyshwon in FIG. 11. The convergent sides 160, 162 of each piston face 150,I52, 154, 156 allow centrifugal force, resulting from rotary motion ofrotary pistons 60, 62, to assist sealing engagement between compressionrings 161 and piston cavity walls 159.

Lubrication of the phasing apparatus here disclosed may be done in anyconventional manner. One method is to provide an oil bath in phasingcavity 54. To provide a uniform oil level on both sides of phasingmember 80, an oil passage opening 162 may be used as shown in FIG. 3. Ofcourse, other methods such as an oil spray are also possible.

The operation of the phasing apparatus of this invention in combinationwith an iternal combustion engine. will now be described by reference toFIGS. 5, 5A, 6, 6A, 7, 7A, 8 and 8A.

Arrow 160 on FIG. 5 indicates the direction of rotation of both rotarypistons 60, 62 within piston cavity 52. As noted, rotary piston 60 isprovided with a pair of diametrically opposed piston faces 150, 152.Similarly, rotary piston element 62 is provided with a pair ofdiametrically opposed piston faces 154, 156. A first working chamber isdefined between adjacent piston faces 150 and 154 of rotary pistons 60,62. Similarly. a second working chamber 175 is defined be tween adjacentpiston faces I52, I56 of roatary pistons 60, 62. As shown in FIG. 5, theworking chamber 170 contains a combustible mixture in a maximum state ofcompression.

The positioning of two pinions 88A, 88B and their relationship to thephasing opening 82 of phasing member 80. which corresponds to theposition of rotary pistons 60. 62 in FIG. 5, as illustrated by FIG. A.Pinion 88A is connected with piston faces I50, I52 of rotary piston 60which is attached to the inner coaxial shaft piston 64. Rotary motion isimparted to the pinion 88A through the gearing arrangement discussedabove in connection with the inner coaxial piston shaft 64. simi larly.pinion 88B is connected with rotary piston 62 that is connected with theouter coaxial piston shaft 66. The gearing arrangement discussed abovein connection with outer coaxial piston shaft 66 causes rotary motion ofpinion 888 in relation to the phasing opening 82. Angle u. illustratedin FIG. 5A corresponds to the angle between adjacent radial slots 102provided on the first rotary plate 92. Accordingly, angle a remains constant as pinions 88A, 88B traverse the phasing opening 82. Angle h.represents the contact angle between pin ions 88A. 88B and the phasingopening. As will be apparent from an examination of FIGS. 5A, 6A. 7A and8A. the contact angle b varies as the pinions 88A. 88B trinerse phasingopening 82.

Spark plug 48 is positioned such that it communicates with workingchambers I70. 175 when a working chamber has compressed a combustiblemixture to the mtuimum extent permitted by the configuration of phasingopening 82. The spark plug 48 would be posi tioned in communication withfirst working chamber I70, as shown in FIG. 5. Spark plug 48 ignites thecom' pressed combustible mixture in the first working cham ber I70thereby exerting a high pressure on piston faces 150. I54 and causing apower stroke. As will be noted from a comparison of FIGS. 5A and 6A,pinion 88A must traverse a greater arc length of phasing opening 82 thandoes pinion 888 when the rotary plates 92, 94 rotate through an angle of90. Since each pinion is interconnected with a piston face, piston face150 will rotate at a more rapid rate and with increasing mechanicaladiantage within piston cavity 52 than will piston face 154 in responseto the power stroke generated by the detonation of combustible mixturein working chamber 170. Working chamber 170 is shown in FIG. 6 at theend of the power stroke.

Exhaust ports 46 are positioned in the housing from cmcr plate 22 in thearcuate area 180 illustrated in FIGS. 5 through 8 and 10. Similarly.intake ports 44 are positioned on the housing front cover plate 22 alongthe arcuate area 185 which is also illustrated in FIGS. 5 through 8 andI0. Depending upon the operating conditions selected for the engine, itmay be desirable to provide valving for some or all of the inlet ports44 or exhaust port 46 or both. Such valving would be part of thecarburetion system and is thus not shown.

The actual placement and sizing of the ports 44, 46 will determinewhether the rotary pistons will function to compress or expand fluidwhich enters the working chambers I70, 175. Accordingly. when thephasing apparatus is used in a pump or motor, the arcuate positioning ofports 44. 46 may require modification.

The exhaustion of spent combustion products from working chamber 170occurs as piston face moves into the arcuate area I80. It will be notedfrom a comparison of FIGS. 6A and 7A that pinion 883 now must traverse alonger arc length of phasing opening 82 than does pinion 88A.Accordingly. piston face 154 will approach piston face 150 therebycontracting the first working chamber 270 and assisting the exhaust ofcombustion products therefrom. The working chamber 270 in its fullyexhausted condition immediately prior to the intake of a fresh charge ofcombustible mixture is shwon in FIG. 7. Thus, FIG. 7 illustrates thepiston positions at the end of an exhaust stroke.

From a comparison of FIGS. 7A and 8A, it will be seen that pinion 88Amust now increase its rate of rotation relative to the rotation ofpinion 88B in order to traverse the greater arc length between pinionpositions shown in FIGS. 7A and 8A. Accordingly, piston face 150 willmove away from piston face 154 and expand working chamber 170. In sodoing, piston face 150 moves into the arcuate area 185 where inlet ports44 are located. The expansion of the first working chamber betweenpiston faces 150 and I54 creates a low pressure region which sucks in afresh charge of combustible mixture thereby causing an intake stroke.The intake of a new charge of a combustible mixture continues untiltrailing piston face 154 moves out of the arcuate inlet area and thusinterrupts fluid communication between the inlet ports 44 and the firstworking chamber 170.

By comparing FIGS. 8A and 5A, it will be seen that the first workingchamber 170 is compressed by the relative motion between piston faces150 and 154 whose motion is determined by the rate of revolution ofpinions 88A and 888 over the respective arc lengths of phasing opening82. The compression corresponds to a compression stroke of a four cycleengine.

A second working chamber defined between pis ton faces 152 and 156 goesthrough the same intake, compression, power and exhaust strokes as doesthe first working chamber 170. The second working cham' ber I75 however,is out of phase with the first working chamber 170 in the sequence ofstrokes. Thus it is apparent that each revolution of power shaft 42 isaccompanied by two power strokes of the internal combustion engine.

It should be noted that the arcuate inlet area and arcuate exhaust area180 may be varied to control the length of time that the workingchambers 170, I75 communicate with the intake ports 44 and exhaust ports46. By providing the arcuate exhaust area 180 in a relatively smallangle, the residence time of combustion products within a workingchamber after the detonation thereof by the spark plug 48 may besubstantially increased. Such an increase in residence time is effectiveto enhance complete combustion of the combustible mixture and therebydiminish the polluting effect of exhaust products from the engine.

In addition. by injecting fuel directly into working chambers 170, 175near the point of maximum com pression. the phasing apparatus couldcontrol a diesel engine cycle.

At this point. it should be abundantly clear to one skilled in the artthat the shape of the phasing opening 82 makes possible the simple anddurable operation of my invention. In addition, it is clear that phasingopen ing 82 may not be a circular opening, since a circular openingwould not cause the different angular velocities of a pair of pinions88A. 888 which is necessary to create relative motion between rotarypistons 60, 62. However. it will be apparent to those skilled in the artthat an elliptical opening may be used for the phasing opening 82 tocreate relative motion between piston elements 60, 62. The bar bellshape which is illustrated for the phasing opening 82 is merely onevariation of the phasing opening 82 which may be used. The bar bellshape however. provides the maximum compression ratio for the workingchambers 170, 175. The compression ratio may be increased by eitherextending the length of phasing opening 82 or by decreasing the width ofthe phasing opening 82. Naturally, the width of phasing opening 82 canbe decreased only to the point where it is wide enough to allow pinions88 to pass between rotary power shaft 42 and the adjacent phasingopening 82.

When used as an internal combustion engine. the useful work developed bythe variable working chambers 170, 175 is imparted to the rotary powershaft 42 by the variable length lever arm defined between the axis ofpiston shaft rotation and the axis of pinion shafts 90.

Other mechanical arrangements to interconnect the coaxial psiton shafts64. 66 and the rotary plates 92, 94 may be devised without departingfrom the scope of my invention. For example, instead of using the offsetbevel gears as illustrated in the drawings, worm and worm wheelcombinations could be used to transmit the necessary rotary motionbetween the coaxial shafts 64. 66 and the pinions 88.

In addition, instead of using a single off-set splined shaft. a pair ofshorter splined shafts may be used which are coaxially disposed with theappropriate driving gear 70 or 72. In this case each shorter splinedshaft would be provided with a fixed gear to mesh with the driving gear70. 72 of one of the coaxial piston shafts. Simple bevel gears may bethen used since the driving and driven shafts could be coplanar. Theembodiment illustrated in the drawings. however, is the preferredembodiment.

One advantage of this invention is the placement of the cooling cavity56 between the piston cavity 52 and the phasing cavity 54. The phasingcavity 54 is provided with lubricating oil which is thus cooled by theliquid provided in cooling cavity 56.

A further advantage of my invention is that centrifugal force caused bythe rotation of rotary plates 92, 94 acts on the pinions 88 to assisttheir engagement with the phasing opening 82.

Dynamic balancing of the apparatus may be quickly and efficientlyaccomplished in view of the placement of balancing means hereindescribed.

The advantage of a smooth. continuous rotary power otput is madepossible by the oscillatory motion of both rotary pistons. Since bothpistons have a basic rotary motion in the same direction. energy whichmight th erwise be lost in pure reciprocating motion is substan tiallyreduced.

Moreover, the disclosed apparatus is simple yet durable. The partsrequired are either readily available offthe-shelf items or are partswhich may be inexpensively produced.

Positioning of inlet and outlet ports advantageously allows control ofcombustion product residence time within the working chamber. Thiscontrol can be used to substantially reduce atmospheric pollutants.

Shaping of the combustion chamber and rotary piston faces advantageouslyallows centrifugal force acting on compression rings to assist thesealing function of those rings.

In addition, the positioning of the phasing apparatus adjacent to thepiston cavity with a portion of the cooling jacket therebetween gives anadded advantage in that lubricating oil in the phasing cavity can becooled simultaneously with the piston cavity.

While the detailed description above describes a preferred embodiment ofthis invention, it is not meant to be limitation of the scope of theinvention which is given by the claims appended hereto. Accordingly,this invention is defined by the claims. and all modifications andequivalents of the claims are expressly intended to be within the scopeof the invention.

What is claimed is:

1. A phasing mechanism for a pair of rotary pistons comprising:

a pair of coaxial piston shafts. each of said piston shafts connected toone of said pair of rotary pistons;

a rotary power shaft coaxially aligned with said pair of coaxial pistonshafts;

a phasing member provided with a phasing opening. said phasing membercoaxially disposed about said rotary power shaft. said phasing openinghaving a predetermined shape which determines relative motion of saidpair of rotary pistons;

at least one pair of rotary members each being constrained to moveradially with respect to the axis of said rotary power shaft. each saidrotary member engaging said phasing opening at a location spa tiallyseparated from the location at which the other of said at least one pairof rotary members engages said phasing opening;

at least one tensioned band having one end carried by one of said pairof rotary members and the other end carried by the second of said pairof rotary members and being operable to resiliently urge said pair ofrotary members radially outwardly into engagement with said phasingopening; and,

means for interconnecting said pair of coaxial piston shafts and saidrotary power shaft, said interconnecting means carrying said at leastone pair of rotary members. said interconnecting means permittingrelative motion between said coaxial piston shafts and also permittingrelative motion between said coaxial piston shafts and said rotary powershaft.

2. The phasing mechanism of claim 1 wherein:

said phasing member comprises a curvilinear internal ring gear.

3. The phasing mechanism of claim 1 wherein:

said interconnecting means includes a pair of rotary plates disposedadjacent said phasing member and connected to said rotary power shaft,each of said rotary plates provided a radial slot for each of said atleast one pair of rotary members.

4. The phasing mechanism of claim 1 wherein:

said interconnecting means includes a pair of rotary plates. each plateporvided with at least one pair of perpendicular radial slots, saidradial slots of one said plate being aligned with said radial slots ofthe other said plate, said rotary plates connected to said rotary shaft;

said phasing member comprises a curvilinear internal ring gear disposedadjacent said pair of rotary plates;

said at least one pair of rotary members being pinions which mesh withsaid curvilinear internal ring gear, each of said at least one pair ofpinions constrained to move radially with respect to said pair of rotaryplates, each of said at least one pair of perpendicular radial slots ofsaid pair of rotary plates; and

said interconnecting means including means for correlating the rotationof said at least one pair of pinions and said pair of coaxial pistonshafts such that said rotary plates make one full revolution for eachfull revolution of said pair of coaxial piston shafts.

5. The phasing mechanism of claim 4 wherein:

each of said pair of rotary plates includes two pairs of symmetricallydisposed perpendicularly aligned slots; and

two pairs of rotating pinions are provided, each pinion being carried byone of said perpendicularly aligned radial slots.

6. The phasing mechanism of claim 4 wherein:

said curvilinear internal ring gear defines a generally barbellshapedopening.

7. A rotary power device comprising:

a housing which defines a phasing cavity and a piston cavity;

a pair of rotary piston elements mounted within said piston cavity;

a pair of coaxial piston shafts, one end of each said pair of coaxialpiston shafts connected to one of said rotary piston elements;

rotary power shaft coaxially aligned with said pair of coaxial pistonshafts and having one end disposed within said phasing cavity;

a phasing member provided with a phasing opening, said phasing membercoaxially disposed about said rotary power shaft within said phasingcavity, said phasing opening having a predetermined shape whichdetermines relative motion of said pair of rotary piston elements:

at least one pair of rotary members each being constrained to moveradially with respect to the axis of said rotary power shaft, each saidrotary member engaging said phasing opening at a location spatiallyseparated from the location at which the other of said at least one pairof rotary members engages said phasing opening;

at least one tensioned band having one end carried by one of said pairof rotary members and the other end carried by the second of said pairof rotary members and being operable to resiliently urge said pair ofrotary members radially outwardly into engagement with said phasingopening; and.

means for interconnecting said pair of coaxial piston shafts and saidrotary power shaft. said interconnecting means carrying said at leastone pair of rotary members, said interconnecting means permittingrelative motion between said coaxial piston shafts and also permittingrelative motion between said coaxial piston shafts and said rotary powershaft.

8. The rotary power device of claim 7 wherein:

said interconnecting means includes a pair of rotary plates each ofwhich is provided with at least one pair of perpendicularly alignedradial slots, each of said rotary plates being attached to said rotarypower shaft and said at least one pair of perpendicular radial slots ofone rotary plate being aligned with said at least one pair ofperpendicular radial slots of the second of said rotary plates;

said phasing member comprises a curvilinear internal ring gear connectedto said housing and disposed adjacent to said rotary plates;

said at least one pair of rotary members are pinions which mesh withsaid internal curvilinear ring gear; and,

said interconnecting means constrains said rotary plates to make onecomplete revolution for each complete revolution of said pair of coaxialpiston shafts:

9. The rotary power device of claim 8 wherein:

the cross-section of each said piston element includes a pair ofstraight converging sides which are tangent to a generally circular endportion; and

said piston cavity is provided with a cross-section similar to the shapeof said piston elements.

10. The rotary power device of claim 8 wherein:

said housing also defines a cooling jacket which surrounds said pistoncavity, said cooling jacket being disposed partially between saidphasing cavity and said piston cavity.

11. A phasing mechanism for a pair of rotary pistons comprising:

a pair of coaxial piston shafts, each of said piston shafts connected toone of said pair of rotary pistons;

a rotary power shaft coaxially aligned with said pair of coaxial pistonshafts;

a phasing member provided with a phasing opening, said phasing membercoaxially disposed about said rotary power shaft, said phasing openinghaving a predetermined shape which determines relative motion of saidpair of rotary pistons;

at least one pair of rotary members each being constrained to moveradially with respect to the axis of said rotary power shaft, each saidrotary member engaging said phasing opening at a location spa tiallyseparated from the location at which the other of said at least one pairof rotary members engages said phasing opening;

means for interconnecting said pair of coaxial piston shafts and saidrotary power shaft, said interconnecting means carrying said at leastone pair of rotary members, said interconnecting means permittingrelative motion between said coaxial piston shafts and also permittingrelative motion between said coaxial piston shafts and said rotary powershaft;

said interconnecting means includes a pair of rotary plates, each plateprovided with at least one pair of perpendicular radial slots, saidradial slots of one said plate being aligned with said radial slots ofthe other said plate, said rotary plates connected to said rotary shaft;

said phasing member comprises a curvilinear internal ring gear disposedadjacent said pair of rotary plates;

said at least one pair of rotary members being pinions which mesh withsaid curvilinear internal ring gear, each of said at least one pair ofpinions constrained to move radially with respect to said pair of rotaryplates, each of said at least one pair of pinions carried by one of saidat least one pair of perpendicular radial slots of said pair of rotaryplates;

said interconnecting means including means for correlating the rotationof said at least one pair of pinions and said pair of coaxial pistonshafts such that said rotary plates make one full revolution for eachfull revolution of said pair of coaxial piston shafts;

said phasing mechanism includes means for maintaining engagement betweensaid at least one pair of pinions and said curvilinear internal ringgear; and,

said means for maintaining engagement includes a tensioned steel band,one end of which is attached to one of said at least one pair of pinionsthe other end of which is attached to the second of said at least onepair of pinions.

12. The phasing mechanism of claim 11 wherein:

said means of maintaining engagement includes a radially movable pulleydisposed at the radially outermost end of each of said at least one pairof perpendicularly aligned radial slots; and

biasing means urging each of said pulleys radially outward whereby saidsteel band is maintained in a tensioned condition.

13. A phasing mechanism wherein:

a pair of coaxial piston shafts, each of said piston shafts connected toone of said pair of rotary pistons; a rotary power shaft coaxiallyaligned with said pair of coaxial piston shafts;

a phasing member provided with a phasing opening, said phasing membercoaxially disposed about said rotary power shaft, said phasing openinghaving a predetermined shape which determines relative motion of saidpair of rotary pistons;

at least one pair of rotary members each being constrained to moveradially with respect to the axis of said rotary power shaft, each saidrotary member engaging said phasing opening at a location spatiallyseparated from the location at which the other of said at least one pairof rotary members engages said phasing opening;

means for interconnecting said pair of coaxial piston shafts and saidrotary power shaft, said interconnecting means carrying said at leastone pair of rotary members, said interconnecting means permittingrelative motion between said coaxial piston shafts and also permittingrelative motion between said coaxial piston shafts and said rotary powershaft;

said interconnecting means includes a pair of rotary plates, each plateprovided with at least one pair of perpendicular radial slots, saidradial slots of one said plate being aligned with said radial slots ofthe other said plate, said rotary plates connected to said rotary shaft;

said phasing member comprises a curvilinear internal ring gear disposedadjacent said pair of rotary plates;

said at least one pair of rotary members being pinions which mesh withsaid curvilinear internal ring gear, each of said at least one pair ofpinions constrained to move radially with respect to said pair of rotaryplates, each of said at least one pair of pinions carried by one of saidat least one pair of perpendicu lar radial slots of said pair of rotaryplates;

said interconnecting means including means for correlating the rotationof said at least one pair of pinions and said pair of coaxial pistonshafts such that said rotary plates make one full revolution for eachfull revolution of said pair of coaxial piston shafts;

said phasing mechanism includes means for maintaining engagement betweensaid at least one pair of pinions and said curvilinear internal ringgear;

said means for correlating the rotation of said pinions and said pair ofcoaxial piston shafts includes a pair of driving gears, one of saiddriving gears connected to one of said pair of coaxial piston shafts,the other said driving gear being connected to the other of said coaxialpiston shafts;

at least one pair of perpendicualr rotary shafts, each of which isrotatably mounted on one of said rotat ing plates;

a pair offixed gears, each of which is mounted on one of said at leastone pair of perpendicular rotary shafts approximately midway between theends thereof;

at least one pair of translating gears, each of which is mounted on oneof said at least one pair of perpendicular rotary shafts between saidfixed gear and an end of said perpendicular rotary shaft such that eachperpendicular rotary shaft has one translating gear thereon;

a pair of pinion driving gears, each pinion driving gear connected withone of said at least one pair of pinions and meshing with one of saidtranslating gears; and

means constraining each said translating gear to slide radially withrespect to said rotary member, each said constraining means beingconnected to one of said at least one pair of pinions.

14. An internal combustion engine comprising:

a. a housing which defines a generally circular cavity.

a phasing cavity and a cooling jacket which is partially interposedbetween said phasing cavity and said generally circular cavity,

a first and a second rotary piston element each disposed within saidgenerally circular cavity;

b. each said rotary piston element comprising:

two diametrically opposed piston faces, each said piston face having apair of straight converging sides and a generally curved end, a segmentshaped skirt defining two radial edges depending from each said pistonface, and compression rings provided on each said radial edge of saidskirt;

c. an inner coaxial piston shaft attached at one end to said firstrotary piston element;

d. an outer coaxial piston shaft attached at one end to said secondrotary piston element and coaxially disposed about said inner coaxialpiston shaft;

e. a first driving bevel gear attached near the second end of said innercoaxial piston shaft and disposed within said phasing cavity;

f. a second driving bevel gear attached to the second end of said outercoaxial piston shaft and disposed within said phasing cavity;

g. a first splined shaft disposed within said phasing cavity andgenerally perpendicularly arranged with respect to said inner coaxialpiston shaft;

h. a first fixed bevel gear disposed approximately midway between theends of said first splined shaft, said first fixed bevel gear meshingwith said first driving bevel gear attached to said inner coaxial pistonshaft;

. a second splined shaft disposed within said phasing cavity andperpendicularly arranged with respect to said outer coaxial pistonshaft;

. a second fixed bevel gear disposed approximately l. a curvilinearinternal ring gear disposed within said phasing cavity;

in. a second rotary plate provided with four radial perpendicular slotsand disposed within said phasing cavity such that said curvilinearinternal ring gear is between said first rotary plate and said secondrotary plate, said radial slots of said first rotary plate and saidradial slots of said second rotary plate being aligned with each other;

7 a rotary power shaft, one end of which protrudes from said housing,the other end of which is attached to both said first and second rotaryplates; four pinions, each of which meshes with the curvi linearinternal ring gear;

four pinion shafts. one of said pinions being mounted on each of saidpinion shafts, one end of said pinion shaft engaging one of said radialslots in said first rotary plate and the second end of said pinion shaftextending through the aligned radial slot of second rotary plate;

carriage means provided in each radial slot of said first and secondrotary plates for engaging said pinion shaft extending therethrough andfor constraining said pinion shaft to move in a radial direction withinsaid slot;

a pinion bevel gear provided on the first end of each of said fourpinion shafts;

. a first translating bevel gear which is slidably mounted on said firstsplined shaft between said first fixed bevel gear and one end of saidfirst splined shaft, said first translating bevel gear meshing with thefirst said pinion bevel gear;

. a second translating bevel gear which is slidably mounted on saidfirst splined shaft between said first fixed bevel gear and a second endof said first splined shaft, said second translating gear meshing withthe second said pinion bevel gear;

a third translating bevel gear which is slidably mounted on said secondsplined shaft between said second fixed bevel gear and one end of saidsecond splined shaft, said third translating gear meshing with the thirdsaid pinion bevel gear;

. a fourth translating bevel gear which is slidably mounted on saidsecond splined shaft between said second fixed bevel gear and the otherend of said second splined shaft, said fourth translating gear meshingwith the fourth said pinion bevel gear;

. a band pulley positioned at the radially outermost end of each saidradial slots of said first rotary plate;

. a first tensioning band being attached at one end to the first pinionshaft and attached at the other end to the second pinion shaft andpassing over two said band pulleys each disposed at the end of twoadjacent perpendicular radial slots;

a second tensioning band attached at one end to the third pinion shaftand attached at the other end to the fourth pinion shaft and passingover the two other said band pulleys each disposed at the end of the tworemaining adjacent perpendicular slots; and

. pulley tensioning means disposed radially inwardly of each said bandpulley for tensioning each said tensioning band when said pinionstraverse the curvilinear internal ring gear.

1. A phasing mechanism for a pair of rotary pistons comprising: a pairof coaxial piston shafts, each of said piston shafts connected to one ofsaid pair of rotary pistons; a rotary power shaft coaxially aligned withsaid pair of coaxial piston shafts; a phasing member provided with aphasing opening, said phasing member coaxially disposed about saidrotary power shaft, said phasing opening having a predetermined shapewhich determines relative motion of said pair of rotary pistons; atleast one pair of rotary members each being constrained to move radiallywith respect to the axis of said rotary power shaft, each said rotarymember engaging said phasing opening at a location spatially separatedfrom the location at which the other of said at least one pair of rotarymembers engages said phasing opening; at least one tensioned band havingone end carried by one of said pair of rotary members and the other endcarried by the second of said pair of rotary members and being operableto resiliently urge said pair of rotary members radially outwardly intoengagement with said phasing opening; and, means for interconnectingsaid pair of coaxial piston shafts and said rotary power shaft, saidinterconnecting means carrying said at least one pair of rotary members,said interconnecting means permitting relative motion between saidcoaxial piston shafts and also permitting relative motion between saidcoaxial piston shafts and said rotary power shaft.
 2. The phasingmechanism of claim 1 wherein: said phasing member comprises acurvilinear internal ring gear.
 3. The phasing mechanism of claim 1wherein: said interconnecting means includes a pair of rotary platesdisposed adjacent said phasing member and connected to said rotary powershaft, each of said rotary plates provided a radial slot for each ofsaid at least one pair of rotary members.
 4. The phasing mechanism ofclaim 1 wherein: said interconnecting means includes a pair of rotaryplates, each plate porvided with at least one pair of perpendicularradial slots, said radial slots of one said plate being aligned withsaid radial slots of the other said plate, said rotary plates connectedto said rotary shaft; said phasing member comprises a curvilinearinternal ring gear disposed adjacent said pair of rotary plates; said atleast one pair of rotary members being pinions which mesh with saidcurvilinear internal ring gear, each of said at least one pair ofpinions constrained to move radially with respect to said pair of rotaryplates, each of said at least one pair of perpendicular radial slots ofsaid pair of rotary plates; and said interconnecting means includingmeans for correlating the rotation of said at least one pair of pinionsand said pair of coaxial piston shafts such that said rotary plates makeone full revolution for each full revolution of said pair of coaxialpiston shafts.
 5. The phasing mechanism of claim 4 wherein: each of saidpair of rotary plates includes two pairs of symmetrically disposedperpendicularly aligned slots; and two pairs of rotating pinions areprovided, each pinion being carried by one of said perpendicularlyaligned radial slots.
 6. The phasing mechanism of claim 4 wherein: saidcurvilinear internal ring gear defines a generally barbell-shapedopening.
 7. A rotary power device comprising: a housing which defines aphasing cavity and a piston cavity; a pair of rotary piston elementsmounted within said piston cavity; a pair of coaxial piston shafts, oneend of each said pair of coaxial piston shafts connected to one of saidrotary piston elements; a rotary power shaft coaxially aligned with saidpair of coaxial piston shafts and having one end disposed within saidphasing cavity; a phasing member provided with a phasing opening, saidphasing member coaxially disposed about said rotary power shaft withinsaid phasing cavity, said phasing opening having a predetermined shapewhich determines relative motion of said pair of rotary piston elements;at least one pair of rotary members each being constrained to moveradially with respect to the axis of said rotary power shaft, each saidrotary member engaging said phasing opening at a location spatiallyseparated from the location at which the other of said at least one pairof rotary members engages said phasing opening; at least one tensionedband having one end carried by one of said pair of rotary members andthe other end carried by the second of said pair of rotary members andbeing operable to resiliently urge said pair of rotary members radiallyoutwardly into engagement with said phasing opening; and, means forinterconnecting said pair of coaxial piston shafts and said rotary powershaft, said interconnecting means carrying said at least one pair ofrotary members, said interconnecting means permitting relative motionbetween said coaxial piston shafts and also permitting relative motionbetween said coaxial piston shafts and said rotary power shaft.
 8. Therotary power device of claim 7 wherein: said interconnecting meansincludes a pair of rotary plates each of which is provided with at leastone pair of perpendicularly aligned radial slots, each of said rotaryplates being attached to said rotary power shaft and said at least onepair of perpendicular radial slots of one rotary plate being alignedwith said at least one pair of perpendicular radial slots of the secondof said rotary plates; said phasing member comprises a curvilinearinternal ring gear connected to said housing and disposed adjacent tosaid rotary plates; said at least one pair of rotary members are pinionswhich mesh with said internal curvilinear ring gear; and, saidinterconnecting means constrains said rotary plates to make one completerevolution for each complete revolution of said pair of coaxial pistonshafts.
 9. The rotary power device of claim 8 wherein: the cross-sectionof each said piston element includes a pair of straight converging sideswhich are tangent to a generally circular end portion; and said pistoncavity is provided with a cross-section similar to the shape of saidpiston elements.
 10. The rotary power device of claim 8 wherein: saidhousing also defines a cooling jacket which surrounds said pistoncavity, said cooling jacket being disposed partially between saidphasing cavity and said piston cavity.
 11. A phasing mechanism for apair of rotary pistons comprising: a pair of coaxial piston shafts, eachof said piston shafts connected to one of said pair of rotary pistons; arotary power shaft coaxially aligned with said pair of coaxial pistonshafts; a phasing member provided with a phasing opening, said phasingmember coaxially disposed about said rotary power shaft, said phasingopening having a predetermined shape which determines relative motion ofsaid pair of rotary pistons; at least one pair of rotary members eachbeing constrained to move radially with respect to the axis of saidrotary power shaft, each said rotary member engaging said phasingopening at a location spatially separated from the location at which theother of said at least one pair of rotary members engages said phasingopening; means for interconnecting said pair of coaxial piston shaftsand said rotary power shaft, said interconnecting means carrying said atleast one pair of rotary members, said interconnecting means permittingrelative motion between said coaxial piston shafts and also permittingrelative motion between said coaxial piston shafts and said rotary powershaft; said interconnecting means includes a pair of rotary plates, eachplate provided with at least one pair of perpendicular radial slots,said radial slots of one said plate being aligned with said radial slotsof the other said plate, said rotary plates connected to said rotaryshaft; said phasing member comprises a curvilinear internal ring geardisposed adjacent said pair of rotary plates; said at least one pair ofrotary members being pinions which mesh with said curvilinear internalring gear, each of said at least one pair of pinions constrained to moveradially with respect to said pair of rotary plates, each of said atleast one pair of pinions carried by one of said at least one pair ofperpendicular radial slots of said pair of rotary plates; saidinterconnecting means including means for correlating the rotation ofsaid at least one pair of pinions and said pair of coaxial piston shaftssuch that said rotary plates make one full revolution for each fullrevolution of said pair of coaxial piston shafts; said phasing mechanismincludes means for maintaining engagement between said at least one pairof pinions and said curvilinear internal ring gear; and, said means formaintaining engagement includes a tensioned steel band, one end of whichis attached to one of said at least one pair of pinions the other end ofwhich is attached to the second of said at least one pair of pinions.12. The phasing mechanism of claim 11 wherein: said means of maintainingengagement includes a radially movable pulley disposed at the radiallyoutermost end of each of said at least one pair of perpendicularlyaligned radial slots; and biasing means urging each of said pulleysradially outward whereby said steel band is maintained in a tensionedcondition.
 13. A phasing mechanism wherein: a pair of coaxial pistonshafts, each of said piston shafts connected to one of said pair ofrotary pistons; a rotary power shaft coaxially aligned with said pair ofcoaxial piston shafts; a phasing member provided with a phasing opening,said phasing member coaxially disposed about said rotary power shaft,said phasing opening having a predetermined shape which determinesrelative motion of said pair of rotary pistons; at least one pair ofrotary members each being constrained to move radially with respect tothe axis of said rotary power shaft, each said rotary member engagingsaid phasing opening at a location spatially separated from the locationat which the other of said at least one pair of rotary members engagessaid phasing opening; means for interconnecting said pair of coaxialpiston shafts and said rotary power shaft, said interconnecting meanscarrying said at least one pair of rotary members, said interconnectingmeans permitting relative motion between said coaxial piston shafts andalso permitting relative motion between said coaxial piston shafts andsaid rotary power shaft; said interconnecting means includes a pair ofrotary plates, each plate provided with at least one pair ofperpendicular radial slots, said radial slots of one said plate beingaligned with said radial slots of the other said plate, said rotaryplates connected to said rotary shaft; said phasing member comprises acurvilinear internal ring gear disposed adjacent said pair of rotaryplates; said at least one pair of rotary members being pinions whichmesh with said curvilinear internal ring gear, each of said at least onepair of pinions constrained to move radially with respect to said pairof rotary plates, each of said at least one pair of pinions carried byone of said at least one pair of perpendicular radial slots of said pairof rotary plates; said interconnecting means including means forcorrelating the rotation of said at least one pair of pinions and saidpair of coaxial piston shafts such that said rotary plates make one fullrevolution for each full revolution of said pair of coaxial pistonshafts; said phasing mechanism includes means for maintaining engagementbetween said at least one pair of pinions and said curvilinear internalring gear; said means for correlating the rotation of said pinions andsaid pair of coaxial piston shafts includes a pair of driving gears, oneof said driving gears connected to one of said pair of coaxial pistonshafts, the other said driving gear being connected to the other of saidcoaxial piston shafts; at least one pair of perpendicualr rotary shafts,each of which is rotatably mounted on one of said rotating plates; apair of fixed gears, each of which is mounted on one of said at leastone pair of perpendicular rotary shafts approximately midway between theends thereof; at least one pair of translating gears, each of which ismounted on one of said at least one pair of perpendicular rotary shaftsbetween said fixed gear and an end of said perpendicular rotary shaftsuch that each perpendicular rotary shaft has one translating gearthereon; a pair of pinion driving gears, each pinion driving gearconnected with one of said at least one pair of pinions and meshing withone of said translating gears; and means constraining each saidtranslating gear to slide radially with respect to said rotary member,each said constraining means being connected to one of said at least onepair of pinions.
 14. An internal combustion engine comprising: a. ahousing which defines a generally circular cavity, a phasing cavity anda cooling jacket which is partially interposed between said phasingcavity and said generally circular cavity, a first and a second rotarypiston element each disposed within said generally circular cavity; b.each said rotary piston element comprising: two diametrically opposedpiston faces, each said piston face having a pair of straight convergingsides and a generally curved end, a segment shaped skirt defining tworadial edges depending from each said piston face, and compression ringsprovided on each said radial edge of said skirt; c. an inner coaxialpiston shaft attached at one end to said first rotary piston element; d.an outer coaxial piston shaft attached at one end to said second rotarypiston element and coaxially disposed about said inner coaxial pistonshaft; e. a first driving bevel gear attached near the second end ofsaid inner coaxial piston shaft and disposed within said phasing cavity;f. a second driving bevel gear attached to the second end of said outercoaxial piston shaft and disposed within said phasing cavity; g. a firstsplined shaft disposed within said phasing cavity and generallyperpendicularly arranged with respect to said inner coaxial pistonshaft; h. a first fixed bevel gear disposed approximately midway betweenthe ends of said first splined shaft, said first fixed bevel gearmeshing with said first driving bevel gear attached to said innercoaxial piston shaft; i. a second splined shaft disposed within saidphasing cavity and perpendicularly arranged with respect to said outercoaxial piston shaft; j. a second fixed bevel gear disposedapproximately midway between the ends of said second splined shaft, saidsecond fixed bevel gear meshing with said second bevel gear attached tosaid outer coaxial piston shaft; k. a first rotary plate disposed withinsaid phasing cavity and adapted to rotatably support said first splinedshaft and said second splined shaft, said first rotary plate beingprovided with four radially aligned perpendicular slots; l. acurvilinear internal ring gear disposed within said phasing cavity; m. asecond rotary plate provided with four radial perpendicular slots anddisposed within said phasing cavity such that said curvilinear internalring gear is between said first rotary plate and said second rotaryplate, said radial slots of said first rotary plate and said radialslots of said second rotary plate being aligned with each other; n. arotary power shaft, one end of which protrudes from said housing, theother end of which is attached to both said first and second rotaryplates; o. four pinions, each of which meshes with the curvilinearinternal ring gear; p. four pinion shafts, one of said pinions beingmounted on each of said pinion shafts, one end of said pinion shaftengaging one of said radial slots in said first rotary plate and thesecond end of said pinion shaft extending through the aligned radialslot of second rotary plate; q. carriage means provided in each radialslot of said first and second rotary plates for engaging said pinionshaft extending therethrough and for constraining said pinion shaft tomove in a radial direction within said slot; r. a pinion bevel gearprovided on the first end of each of said four pinion shafts; s. a firsttranslating bevel gear which is slidably mounted on said first splinedshaft between said first fixed bevel gear and one end of said firstsplined shaft, said first translating bevel gear meshing with the firstsaid pinion bevel gear; t. a second translating bevel gear which isslidably mounted on said first splined shaft between said first fixedbevel gear and a second end of said first splined shaft, said secondtranslating gear meshing with the second said pinion bevel gear; u. athird translating bevel gear which is slidably mounted on said secondsplined shaft between said second fixed bevel gear and one end of saidsecond splined shaft, said third translating gear meshing with the thirdsaid pinion bevel gear; v. a fourth translating bevel gear which isslidably mounted on said second splined shaft between said second fixedbevel gear and the other end of said second splined shaft, said fourthtranslating gear meshing with the fourth said pinion bevel gear; w. aband pulley positioned at the radially outermost end of each said radialslots of said first rotary plate; x. a first tensioning band beingattached at one end to the first pinion shaft and attached at the otherend to the second pinion shaft and passing over two said band pulleyseach disposed at the end of two adjacent perpendicular radial slots; y.a second tensioning band attached at one end to the third pinion shaftand attached at the other end to the fourth pinion shaft and passingover the two other said band pulleys each disposed at the end of the tworemaining adjacent perpendicular slots; and z. pulley tensioning meansdisposed radially inwardly of each said band pulley for tensioning eachsaid tensioning band when said pinions traverse the curvilinear internalring gear.